System and method for dynamically assigning routers to hosts through a mediator

• US 6,754,220 B1
• Filed: 05/11/2000
• Issued: 06/22/2004
• Est. Priority Date: 05/31/1999
• Status: Expired due to Term

• Current Assignee: Google LLC (Alphabet Inc.)
• Original Assignee: International Business Machines Corporation
• Inventors: Secondo, Pierre, Thubert, Pascal, Lamberton, Marc, Levy-Abegnoli, Eric
• Primary Examiner(s): Hsu, Alpus H.
• Assistant Examiner(s): Molinari, Michael J
• Application Number:
  US09/568,690
• Time in Patent Office: 1,503 Days
• Field of Search: 370/216, 370/217, 370/218, 370/242, 370/245, 370/401, 370/229, 370/230, 370/230.1, 370/235, 370/237, 370/389, 710/7, 710/20, 710/29, 340/825.01, 340/2.1, 714/1, 714/2, 714/3, 714/4, 709/105, 709/234, 709/235, 709/238, 709/239, 709/249
• US Class Current: 370/401
• CPC Class Codes: H04L 12/2856 Access arrangements, e.g. Internet access asynchronous transfer mode networks H04L12/5601; broadband local area networks H04L12/2801; optical access or distribution networks H04Q11/0067; access to open networks H04L12/5691; digital subscriber line end-user equipment and bit-level processing of data on a PSTN-based network H04M11/00; home network gateways H04L12/2834; wireless access networks H04W
• CPC Class Codes: H04L 12/2876 Handling of subscriber policies group policies management H04L41/0893
• CPC Class Codes: H04L 12/2898 Subscriber equipments DSL modems H04M11/062; cable modems H04L12/2801
• CPC Class Codes: H04L 45/02 Topology update or discovery
• CPC Class Codes: H04L 45/22 Alternate routing
• CPC Class Codes: H04L 45/28 using route fault recovery
• CPC Class Codes: H04L 61/00 Network arrangements, protocols or services for addressing or naming
• CPC Class Codes: H04L 61/10 of different types

Abstract

A method and system are disclosed for dynamically assigning, on a Local Area Network, through a mediator, a plurality of active routers to a plurality of hosts so as to handle hosts data packets destined to remote users not connected on the LAN. Because hosts know only the address of the mediator they must first go through it for being assigned a particular router. When receiving the first request, mediator selects one router among those of the routers that are active and informs the host which may then forward the first packet and all subsequent ones to the selected router. The same is done for each host connected on the LAN. After which mediator is free to reassess the router to host assignment any time if significant changes are observed such as the failure of a router, the removing or the addition of a router to the pool of routers or a drastic modification of the host generated traffic.

Claims

1. A method for dynamically assigning, on a Local Area Network, through a mediator, a plurality of active routers to a plurality of hosts, said mediator, said hosts and said routers having each a unique address on said LAN for handling through said routers, data packets from said hosts destined to remote users not connected on said LAN, said method comprising the steps of;

storing the address of said mediator initially in said hosts as a default address;

upon sending a first data packet from a particular host among said plurality of hosts towards one of said remote users not connected on said LAN;

issuing, from said particular host with said default address, a request for being assigned a particular router among said plurality of active routers;

selecting, in said mediator, on behalf of said particular host, a particular router, among said plurality of active routers;

receiving, in said particular host, instructions from said mediator for using said selected router;

forwarding said first data packet to said selected router;

upon sending subsequent data packets from said particular host towards said remote users not connected on said LAN;

continuing forwarding said data packets to said selected router; and

repeating all herein steps for each host among said plurality of hosts.

2. The method of claim 1 wherein the step of selecting a particular router further includes the step of using any round robin sequence skipping inoperative routers.

3. The method of claim 1 wherein said mediator is monitoring routers activity and where said step of selecting a router further comprises the step of using said router activity as a criterion for choosing a router.

4. The method of claim 1 wherein said mediator is monitoring the number of host generated data packets towards said remote users not connected on said LAN and where said step of selecting a router further comprises the step of using said number of host generated data packets as a criterion for choosing a router.

5. The method of claim 1 wherein the method of dynamically assigning a router to a host is reassessed periodically.

6. The method of claim 1 wherein the method of dynamically assigning a router to a host is reassessed upon determining when a router is becoming inoperative or is becoming operative.

7. The method of claim 1 wherein two mediators which share a database are used, only one of the mediators being active while the other one of the mediators is in standby, said method further including the steps of:

determining which mediator is active;

monitoring said active mediator by said standby mediator; and

taking over the role of active mediator by said standby mediator whenever said active mediator becomes inoperative.

8. The method of claim 1 wherein the steps of issuing a request from a host and receiving instructions for using a router are done with the IP Address Resolution Protocol.

9. A system comprising:

a mediator, a plurality of hosts, and a plurality of routers, the mediator, hosts and routers being coupled on a Local Area Network (LAN), said system comprising logic which dynamically assigns, through said mediator, a plurality of active routers to a plurality of hosts, said mediator, said hosts and said routers having each a unique address on said LAN for handling through said routers, data packets from said hosts destined to remote users not connected on said LAN, said logic being effective to;

store the address of said mediator initially in said hosts as a default address;

upon sending a first data packet from a particular host among said plurality of hosts towards one of said remote users not connected on said LAN;

issue, from said particular host with said default address, a request for being assigned a particular router among said plurality of active routers;

select, in said mediator, on behalf of said particular host, a particular router, among said plurality of active routers;

receive, in said particular host, instructions from said mediator for using said selected router;

forward said first data packet to said selected router;

upon sending subsequent data packets from said particular host towards said remote users not connected on said LAN;

continue forwarding said data packets to said selected router; and

repeating all herein steps for each host among said plurality of hosts.

10. The system of claim 9 wherein the logic which selects a router further includes the use of any round robin sequence skipping inoperative routers.

11. The system of claim 9 wherein said mediator is monitoring routers activity and wherein the logic which selects a router further comprises the use of the router activity as a criterion for choosing a router.

12. The system of claim 9 wherein said mediator is monitoring the number of host generated data packets towards said remote users not connected on said LAN and wherein the logic which selects a router further comprises the use of said number of host generated data packets as a criterion for choosing a router.

13. The system of claim 9 wherein the dynamic assignment of a router to a host is reassessed periodically.

14. The system of claim 9 wherein the dynamic assignment of a router to a host is reassessed upon determining when a router changes states wherein the state is a state in which a router becomes inoperative or a state in which a router becomes operative.

15. The system of claim 9 wherein two mediators which share a database are used, only one of the mediators being active while the other one of the mediators is in standby, wherein the logic is further effective to:

determine which mediator is active;

monitor said active mediator by said standby mediator; and

take over the role of active mediator by said standby mediator whenever said active mediator becomes inoperative.

16. The system of claim 9 wherein the logic which issues a request from a host and receives instructions for using a router are done with the IP Address Resolution Protocol.

17. A product comprising:

a computer usable medium having computer readable program code stored therein for dynamically assigning, on a Local Area Network, through a mediator, a plurality of active routers to a plurality of hosts, said mediator, said hosts and said routers having each a unique address on said LAN for handling through said routers, data packets from said hosts destined to remote users not connected on said LAN, the computer readable program code in said program product being effective when executing to;

store the address of said mediator initially in said hosts as a default address;

upon sending a first data packet from a particular host among said plurality of hosts towards one of said remote users not connected on said LAN;

issue, from said particular host with said default address, a request for being assigned a particular router among said plurality of active routers;

select, in said mediator, on behalf of said particular host, a particular router, among said plurality of active routers;

receive, in said particular host, instructions from said mediator for using said selected router;

forward said first data packet to said selected router;

upon sending subsequent data packets from said particular host towards said remote users not connected on said LAN;

continue forwarding said data packets to said selected router; and

repeating all herein steps for each host among said plurality of hosts.

18. The system of claim 17 wherein the code which selects a router further includes the use of any round robin sequence skipping inoperative routers.

19. The system of claim 17 wherein said mediator is monitoring routers activity and wherein the code which selects a router further comprises the use of the router activity as a criterion for choosing a router.

20. The system of claim 17 wherein said mediator is monitoring the number of host generated data packets towards said remote users not connected on said LAN and wherein the code which selects a router further comprises the use of said number of host generated data packets as a criterion for choosing a router.

21. The system of claim 17 wherein the dynamic assignment of a router to a host is reassessed periodically.

22. The system of claim 17 wherein the dynamic assignment of a router to a host is reassessed upon determining when a router changes states wherein the state is a state in which a router becomes inoperative or a state in which a router becomes operative.

23. The system of claim 17 wherein two mediators which share a database are used, only one of the mediators being active while the other one of the mediators is in standby, wherein the code is further effective to:

determine which mediator is active;

monitor said active mediator by said standby mediator; and

take over the role of active mediator by said standby mediator whenever said active mediator becomes inoperative.

24. The system of claim 17 wherein the code which issues a request from a host and receives instructions for using a router are done with the IP Address Resolution Protocol.